auto-version-bump.yml

name: Auto Version Bump

on:
  pull_request:
    types:
      - opened
      - synchronize
      - reopened
      - closed
    branches:
      - main

permissions:
  contents: write

jobs:
  bump-version:
    if: github.event.action != 'closed' && github.event.pull_request.head.repo.full_name == github.repository
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          ref: ${{ github.event.pull_request.head.ref }}
          fetch-depth: 0
          token: ${{ secrets.GITHUB_TOKEN }}

      - name: Determine bump type
        id: bump
        env:
          PR_BODY: ${{ github.event.pull_request.body }}
        run: |
          BUMP="patch"
          if echo "$PR_BODY" | grep -qiE '^\s*-\s*\[[xX]\]\s*Major'; then
            BUMP="major"
          elif echo "$PR_BODY" | grep -qiE '^\s*-\s*\[[xX]\]\s*Minor'; then
            BUMP="minor"
          fi

          echo "Resolved bump type: $BUMP"
          echo "type=$BUMP" >> "$GITHUB_OUTPUT"

      - name: Compute version relative to latest main
        id: apply
        run: |
          git fetch origin main
          BASE_VERSION=$(git show origin/main:package.json | node -e "process.stdout.write(JSON.parse(require('fs').readFileSync(0,'utf8')).version)")

          node -e "
            const fs = require('fs');
            const p = JSON.parse(fs.readFileSync('package.json', 'utf8'));
            p.version = '$BASE_VERSION';
            fs.writeFileSync('package.json', JSON.stringify(p, null, 2) + '\n');
          "

          npm version ${{ steps.bump.outputs.type }} --no-git-tag-version
          echo "version=$(node -p "require('./package.json').version")" >> "$GITHUB_OUTPUT"

      - name: Commit and push if version changed
        env:
          VERSION: ${{ steps.apply.outputs.version }}
          HEAD_REF: ${{ github.event.pull_request.head.ref }}
        run: |
          if git diff --quiet -- package.json package-lock.json; then
            echo "package.json already at the correct version, nothing to push"
            exit 0
          fi

          git config user.name "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"
          git add package.json package-lock.json
          git commit -m "chore: bump version to $VERSION"
          git push origin "HEAD:$HEAD_REF"

  tag-release:
    if: github.event.action == 'closed' && github.event.pull_request.merged == true
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          ref: main
          fetch-depth: 0
          token: ${{ secrets.GITHUB_TOKEN }}

      - name: Tag the merged version
        run: |
          VERSION=$(node -p "require('./package.json').version")
          if git rev-parse "v$VERSION" >/dev/null 2>&1; then
            echo "Tag v$VERSION already exists, skipping tag creation"
          else
            git config user.name "github-actions[bot]"
            git config user.email "github-actions[bot]@users.noreply.github.com"
            git tag "v$VERSION"
            git push origin "v$VERSION"
          fi